What you'll learn:
- Write character device driver from scratch
- Understand the various file operations provided by character driver
Updated on Oct 10: Added Downloads section
What will you learn from this course?
Introduction to character drivers
What is device number and device file
Allocating device number - statically and dynamically
Creating device file - Manually(mknod) and automatically (udev)
Registering character device and its file operation with Kernel
Copying data from user space to kernel space and vice versa
Understanding the various structures - struct file and struct inode
Implementation of open, release, read, write, llseek, ioctl file operations
How to create multiple device nodes and add support for private data
Flow of write system call from kernel system call entry point to driver write file operations
Handling all the error cases in ioctl implementation
Sending a signal to user space from kernel space
Various access control mechanisms and capabilities
Misc Driver
API's covered in this course:
MAJOR
MINOR
MKDEV
register_chrdev_region
alloc_chrdev_region
class_create
device_create
class_destroy
device_destroy
unregister_chrdev_region
imajor
iminor
copy_from_user
copy_to_user
put_user
get_user
print_dev_t
format_dev_t
strnlen_user
container_of
access_ok
Commands used in this course:
mknod
udevadm monitor
